In recent years, image processing technologies using a computer have been widely used. Among the image processing technologies is a technique of generating an image of three-dimensional space. As an example, in three-dimensional computer graphics, a modeled object is placed in virtual three-dimensional space based on settings of a scene layout, and an image of the virtual three-dimensional space is generated by rendering.
The technique of generating an image of three-dimensional space is, for example, used in navigation systems. Specifically, some navigation systems can display an image similar to a scene which the user actually views as a three-dimensional map. For such navigation systems, various techniques of improving the usability for the user have been proposed.
For example, Patent Literature 1 discloses a technique of drawing a structural object located closer to the user than a point of interest, such as a target building, in a special form, such as a wire frame, translucent form, etc., in order to allow the user to easily recognize the object of interest and the surrounding environment.